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Complex Activity (complex + activity)
Selected AbstractsManaging Interdependence: The Effects of Outsourcing Structure on the Performance of Complex Projects,DECISION SCIENCES, Issue 1 2008Pamsy P. Hui ABSTRACT The outsourcing of complex activities has become a common organizational practice. Yet very little research has focused on the implications of how these activities are divided up among outsourcing partners. Drawing on structural contingency theory, we argue that: (1) because activities within stages of complex projects are highly interdependent, outsourcing structures where owner firms do not maintain high levels of dominance over the activities that are performed will pose control and coordination challenges, leading to poor project performance; (2) the adverse effects of poorly structured outsourcing arrangements will spill over to subsequent project stages when activities are interdependent across project stages; and (3) dividing activities among large numbers of contractors or distributing work evenly among contractors exacerbates coordination and control problems further contributing to poor project performance. Our empirical analysis of 323 capital facility construction projects supports our predictions. Overall, these results provide strong evidence that some outsourcing structures are more costly than others and that because of the nature of complex projects the detrimental effects of poorly structured outsourcing are often not completely observable at the time activities are completed. We discuss the implications of our findings for capital construction and for outsourcing more generally. [source] Decreased activities of mitochondrial respiratory chain complexes in non-mitochondrial respiratory chain diseasesDEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 2 2006Joannie Hui MBBS The aim of this study was to illustrate the difficulties in establishing a diagnosis of mitochondrial respiratory chain (MRC) disorders based on clinical grounds in combination with intermediate activities of the MRC enzyme complexes. We reviewed retrospectively all medical and laboratory records of patients initially considered likely to have MRC disorders on clinical grounds, and subsequently diagnosed with other disorders (n=20; 11 males, 9 females). Data were retrieved from hospital records, referral letters, and results of enzymatic analysis at a reference laboratory. Clinical symptoms included developmental delay, epilepsy, hypotonia, movement disorder, spastic quadriplegia, tetany, microcephaly, visual problems, carpopedal spasms, dysmorphism, hearing loss, muscle weakness and rhabdomyolysis, and fulminant hepatitis. Blood and cerebrospinal fluid lactate levels were elevated in 13/20 and 9/20 respectively. One or more MRC complex activities (expressed as ratios relative to citrate synthase and/or complex II activity) were less than 50% of control mean activity in 11/20 patients (including patients with deficiencies of pyruvate dehydrogenase complex, pantothenate kinase, holocarboxylase synthetase, long-chain hydroxy acyl-CoA dehydrogenase, molybdenum co-factor, and neonatal haemochromatosis). One patient had a pattern suggestive of mitochondrial proliferation. We conclude that intermediate results of MRC enzymes should be interpreted with caution and clinicians should be actively looking for other underlying diagnoses. [source] Post-stroke depression, executive dysfunction and functional outcomeEUROPEAN JOURNAL OF NEUROLOGY, Issue 3 2002T. Pohjasvaara The early diagnosis of vascular cognitive impairment has been challenged and executive control function has been suggested to be a rational basis for the diagnosis of vascular dementia. We sought to examine the correlates of executive dysfunction in a well-defined stroke cohort. A group of 256 patients from a consecutive cohort of 486 patients with ischaemic stroke, aged 55,85 years, was subjected to a comprehensive neuropsychological examination 3,4 months after ischaemic stroke and 188 of them in addition to detailed psychiatric examination. Basic and complex activities of daily living (ADLs) (bADLs and cADLs) post-stroke were assessed. The DSM-III-R criteria were used for the diagnosis of the depressive disorders. Altogether 40.6% (n=104) of the patients had executive dysfunction. The patients with executive dysfunction were older, had lower level of education, were more often dependent, did worse in bADLs and cADLs, had more often DSM-III dementia, had worse cognition as measured by Mini Mental State Examination (MMSE) and were more depressed as measured by the BECK depression scale, but not with the more detailed psychiatric evaluation. They had more often stroke in the anterior circulation and less often in the posterior circulation. The independent correlates of executive dysfunction were cADLs (OR 1.1, 95% CI 1.03,1.16), each point of worsening in cognition by MMSE (OR 1.7, 95% CI 1.42,1.97) and stroke in the posterior circulation area (OR 0.4, 95% CI 0.18,0.84). Clinically significant executive dysfunction is frequent after ischaemic stroke and is closely connected with cADLs and to overall cognitive status but could be distinguished from depression by detailed neuropsychological examination. Executive measures may detect patients at risk of dementia and disability post-stroke. [source] ,-Amyloid inhibits integrated mitochondrial respiration and key enzyme activitiesJOURNAL OF NEUROCHEMISTRY, Issue 1 2002C. S. Casley Abstract Disrupted energy metabolism, in particular reduced activity of cytochrome oxidase (EC 1.9.3.1), ,-ketoglutarate dehydrogenase (EC 1.2.4.2) and pyruvate dehydrogenase (EC 1.2.4.1) have been reported in post-mortem Alzheimer's disease brain. ,-Amyloid is strongly implicated in Alzheimer's pathology and can be formed intracellularly in neurones. We have investigated the possibility that ,-amyloid itself disrupts mitochondrial function. Isolated rat brain mitochondria have been incubated with the ,-amyloid alone or together with nitric oxide, which is known to be elevated in Alzheimer's brain. Mitochondrial respiration, electron transport chain complex activities, ,-ketoglutarate dehydrogenase activity and pyruvate dehydrogenase activity have been measured. ,-Amyloid caused a significant reduction in state 3 and state 4 mitochondrial respiration that was further diminished by the addition of nitric oxide. Cytochrome oxidase, ,-ketoglutarate dehydrogenase and pyruvate dehydrogenase activities were inhibited by ,-amyloid. The Km of cytochrome oxidase for reduced cytochrome c was raised by ,-amyloid. We conclude that ,-amyloid can directly disrupt mitochondrial function, inhibits key enzymes and may contribute to the deficiency of energy metabolism seen in Alzheimer's disease. [source] Inputs and Outcomes of Outdoor Management Development: Of Design, Dogma and DissonanceBRITISH JOURNAL OF MANAGEMENT, Issue 4 2007Philip J. Jones Although it is now a multi-million pound international industry, there is continuing scepticism about the benefits of Outdoor Management Development (OMD). This study investigates the impact of participation in an archetypal example of OMD on a cohort of junior managers (n=19). Participants reported changes in a variety of attitudes including, their opinions of themselves, team-working and the theoretical frameworks used to underpin the programme. Analysis of individuals' accounts found associations between participation in particular forms of outdoor training activities and changes in certain categories of attitude. Cognitive dissonance theory is used as a framework to explain these changes. More specifically, we contend that task selection and review-style choices made by providers and sponsors significantly influenced the reactions, sense-making processes and training outcomes reported by participants. This study challenges the design of contemporary OMD programmes that privileges a linear, incremental view of development where one starts with simple tasks of short duration and gradually progresses to longer and more complex activities. [source] A mitochondrial ATPase 6 mutation is associated with Leigh syndrome in a family and affects proton flow and adenosine triphosphate output when modeled in Escherichia coliACTA PAEDIATRICA, Issue 2004R Carrozzo A multidisciplinary strategy was used to identify the molecular defect in a family with Leigh syndrome (LS). The propositus presented severe developmental delay, an ataxic-spastic gait and seizures. She died at 3.5 y of age from cardiorespiratory arrest. Postmortem examination disclosed pathological features typical of LS. A 12-y-old sister is affected with the same disease. Respiratory chain enzyme complex activities in skeletal muscle biopsy were normal. Adenosine triphosphate (ATP) synthesis during oxidative phosphorylation in skin fibroblasts mitochondria showed a severely hampered ATP production. Mitochondrial DNA sequencing revealed a new mutation in the ATPase 6 gene (T9176G). Site-directed mutagenesis in Escherichia coli strains was used to measure H+ pumping and ATP synthesis. Results were comparable to findings obtained in human cells. These data corroborate the use of E. coli strains as a feasible "animal" model for functional studies in pathogenic mutations of the ATPase 6 gene. [source] Early processing in the human lateral occipital complex is highly responsive to illusory contours but not to salient regionsEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 10 2009Marina Shpaner Abstract Human electrophysiological studies support a model whereby sensitivity to so-called illusory contour stimuli is first seen within the lateral occipital complex. A challenge to this model posits that the lateral occipital complex is a general site for crude region-based segmentation, based on findings of equivalent hemodynamic activations in the lateral occipital complex to illusory contour and so-called salient region stimuli, a stimulus class that lacks the classic bounding contours of illusory contours. Using high-density electrical mapping of visual evoked potentials, we show that early lateral occipital cortex activity is substantially stronger to illusory contour than to salient region stimuli, whereas later lateral occipital complex activity is stronger to salient region than to illusory contour stimuli. Our results suggest that equivalent hemodynamic activity to illusory contour and salient region stimuli probably reflects temporally integrated responses, a result of the poor temporal resolution of hemodynamic imaging. The temporal precision of visual evoked potentials is critical for establishing viable models of completion processes and visual scene analysis. We propose that crude spatial segmentation analyses, which are insensitive to illusory contours, occur first within dorsal visual regions, not the lateral occipital complex, and that initial illusory contour sensitivity is a function of the lateral occipital complex. [source] Breathing rhythms and emotionsEXPERIMENTAL PHYSIOLOGY, Issue 9 2008Ikuo Homma Respiration is primarily regulated for metabolic and homeostatic purposes in the brainstem. However, breathing can also change in response to changes in emotions, such as sadness, happiness, anxiety or fear. Final respiratory output is influenced by a complex interaction between the brainstem and higher centres, including the limbic system and cortical structures. Respiration is important in maintaining physiological homeostasis and co-exists with emotions. In this review, we focus on the relationship between respiration and emotions by discussing previous animal and human studies, including studies of olfactory function in relation to respiration and the piriform,amygdala in relation to respiration. In particular, we discuss oscillations of piriform,amygdala complex activity and respiratory rhythm. [source] Modeling the Qo site of crop pathogens in Saccharomyces cerevisiae cytochrome bFEBS JOURNAL, Issue 11 2004Nicholas Fisher Saccharomyces cerevisiae has been used as a model system to characterize the effect of cytochrome b mutations found in fungal and oomycete plant pathogens resistant to Qo inhibitors (QoIs), including the strobilurins, now widely employed in agriculture to control such diseases. Specific residues in the Qo site of yeast cytochrome b were modified to obtain four new forms mimicking the Qo binding site of Erysiphe graminis, Venturia inaequalis, Sphaerotheca fuliginea and Phytophthora megasperma. These modified versions of cytochrome b were then used to study the impact of the introduction of the G143A mutation on bc1 complex activity. In addition, the effects of two other mutations F129L and L275F, which also confer levels of QoI insensitivity, were also studied. The G143A mutation caused a high level of resistance to QoI compounds such as myxothiazol, axoxystrobin and pyraclostrobin, but not to stigmatellin. The pattern of resistance conferred by F129L and L275F was different. Interestingly G143A had a slightly deleterious effect on the bc1 function in V. inaequalis, S. fuliginea and P. megasperma Qo site mimics but not in that for E. graminis. Thus small variations in the Qo site seem to affect the impact of the G143A mutation on bc1 activity. Based on this observation in the yeast model, it might be anticipated that the G143A mutation might affect the fitness of pathogens differentially. If so, this could contribute to observed differences in the rates of evolution of QoI resistance in fungal and oomycete pathogens. [source] Modulation of Alp4 function in Schizosaccharomyces pombe induces novel phenotypes that imply distinct functions for nuclear and cytoplasmic ,-tubulin complexesGENES TO CELLS, Issue 4 2006Hirohisa Masuda The ,-tubulin complex acts as a nucleation unit for microtubule assembly. It remains unknown, however, how spatial and temporal regulation of the complex activity affects microtubule-mediated cellular processes. Alp4 is one of the essential components of the S. pombe,-tubulin complex. We show here that overproduction of a carboxy-terminal form of Alp4 (Alp4C) and its derivatives tagged to a nuclear localization signal or to a nuclear export signal affect localization of ,-tubulin complexes and induces novel phenotypes that reflect distinct functions of nuclear and cytoplasmic ,-tubulin complexes. Nuclear Alp4C induces a Wee1-dependent G2 delay, reduces the levels of the ,-tubulin complex at the spindle pole body, and results in defects in mitotic progression including spindle assembly, cytoplasmic microtubule disassembly, and chromosome segregation. In contrast, cytoplasmic Alp4C induces oscillatory nuclear movement and affects levels of cell polarity markers, Bud6 and Tip1, at the cell ends. These results demonstrate that regulation of nuclear ,-tubulin complex activity is essential for cell cycle progression through the G2/M boundary and M phase, whereas regulation of cytoplasmic ,-tubulin complex activity is important for nuclear positioning and cell polarity control during interphase. [source] The carboxy-terminus of Alp4 alters microtubule dynamics to induce oscillatory nuclear movement led by the spindle pole body in Schizosaccharomyces pombeGENES TO CELLS, Issue 4 2006Hirohisa Masuda Alp4 is an essential component of the S. pombe,-tubulin complex. Overproduction of the carboxy-terminus of Alp4 induces oscillatory nuclear movement led by the spindle pole body (SPB). The movement is not dependent on cytoplasmic dynein dhc1, or kinesin-related proteins pkl1 and klp2. Rates of SPB movement correlate with elongation rates of microtubules (MTs) extending backwards from the moving SPB (backward-extending MTs), showing that pushing forces exerted by backward-extending MTs move the nucleus via the SPB. These backward-extending MTs are more stable than those of control cells and, thus, are able to push the SPB further towards the cell end, inducing nuclear oscillation with larger amplitudes than in control cells. SPB movement is biased towards the new end of the cell where levels of the CLIP170 homolog Tip1 increase, suggesting that the movement is related to MT-mediated cell polarity control. These results demonstrate that the carboxy-terminus of Alp4 alters MT dynamics and induces nuclear oscillation by modulating a nuclear positioning mechanism based on the balance of MT pushing forces, and suggest that regulation of ,-tubulin complex activity is important for controlling MT dynamics and nuclear positioning. [source] Maternal high-fat feeding primes steatohepatitis in adult mice offspring, involving mitochondrial dysfunction and altered lipogenesis gene expression,HEPATOLOGY, Issue 6 2009Kimberley D. Bruce Nonalcoholic fatty liver disease (NAFLD) describes an increasingly prevalent spectrum of liver disorders associated with obesity and metabolic syndrome. It is uncertain why steatosis occurs in some individuals, whereas nonalcoholic steatohepatitis (NASH) occurs in others. We have generated a novel mouse model to test our hypothesis: that maternal fat intake contributes to the development of NAFLD in adult offspring. Female mice were fed either a high-fat (HF) or control chow (C) diet before and during gestation and lactation. Resulting offspring were fed either a C or a HF diet after weaning, to generate four offspring groups; HF/HF, HF/C, C/HF, C/C. At 15 weeks of age, liver histology was normal in both the C/C and HF/C offspring. Kleiner scoring showed that although the C/HF offspring developed nonalcoholic fatty liver, the HF/HF offspring developed NASH. At 30 weeks, histological analysis and Kleiner scoring showed that both the HF/C and C/HF groups had NAFLD, whereas the HF/HF had a more severe form of NASH. Therefore, exposure to a HF diet in utero and during lactation contributes toward NAFLD progression. We investigated the mechanisms by which this developmental priming is mediated. At 15 weeks of age, hepatic mitochondrial electron transport chain (ETC) enzyme complex activity (I, II/III, and IV) was reduced in both groups of offspring from HF-fed mothers (HF/C and HF/HF). In addition, measurement of hepatic gene expression indicated that lipogenesis, oxidative stress, and inflammatory pathways were up-regulated in the 15-week-old HF/C and HF/HF offspring. Conclusion: Maternal fat intake contributes toward the NAFLD progression in adult offspring, which is mediated through impaired hepatic mitochondrial metabolism and up-regulated hepatic lipogenesis. (HEPATOLOGY 2009.) [source] Mitochondrial dysfunction early after traumatic brain injury in immature ratsJOURNAL OF NEUROCHEMISTRY, Issue 5 2007Courtney L. Robertson Abstract Mitochondria play central roles in acute brain injury; however, little is known about mitochondrial function following traumatic brain injury (TBI) to the immature brain. We hypothesized that TBI would cause mitochondrial dysfunction early (<4 h) after injury. Immature rats underwent controlled cortical impact (CCI) or sham injury to the left cortex, and mitochondria were isolated from both hemispheres at 1 and 4 h after TBI. Rates of phosphorylating (State 3) and resting (State 4) respiration were measured with and without bovine serum albumin. The respiratory control ratio was calculated (State 3/State 4). Rates of mitochondrial H2O2 production, pyruvate dehydrogenase complex enzyme activity, and cytochrome c content were measured. Mitochondrial State 4 rates (ipsilateral/contralateral ratios) were higher after TBI at 1 h, which was reversed with bovine serum albumin. Four hours after TBI, pyruvate dehydrogenase complex activity and cytochrome c content (ipsilateral/contralateral ratios) were lower in TBI mitochondria. These data demonstrate abnormal mitochondrial function early (,4 h) after TBI in the developing brain. Future studies directed at reversing mitochondrial abnormalities could guide neuroprotective interventions after pediatric TBI. [source] Business Growth and Performance and the FinancialReporting Practices of Australian Manufacturing SMEsJOURNAL OF SMALL BUSINESS MANAGEMENT, Issue 2 2001Richard G.P. McMahon This article describes an explanatory study of the impact of financial reporting practices upon business growth and performance outcomes amongst small and medium-sized enterprises (SMEs) engaged in manufacturing in Australia. The study is able to establish some statistically significant bivariate associations between the extent and frequency of financial reporting undertaken and certain measures of SME growth and performance. However, the state of financial reporting practices becomes subsumed by other important influences in multivariate analysis. Management is a complex activity affected by a myriad of interacting internal and external factors, and must inevitably be undertaken in an holistic manner in SMEs. Particular practices make a contribution to the whole task without necessarily standing out as all-embracing solutions to problems generally encountered. Thus, it is argued that improved financial reporting should be realistically viewed as simply part of a broader competence in financial management which, taken together with other functional capabilities, is likely to lead to more effective and efficient management of SMEs and significantly improve their prospects. [source] Pharmacodynamics of warfarin in catsJOURNAL OF VETERINARY PHARMACOLOGY & THERAPEUTICS, Issue 6 2000S. A. SMITH The overall purpose of this study was to evaluate the pharmacodynamic response to warfarin in cats. The specific aim was to determine if a log-linear indirect response model (Nagashima et al., 1969) used to describe the in vivo effect of warfarin in humans could be applied to cats. The pharmacokinetics of racemic warfarin were described using a non-compartmental approach. The relationship between prothrombin complex activity (PCA) and normalized prothrombin time (PTR) was defined for feline plasma under our experimental conditions, and determined to be: %PCA=12.38+648 e,PTR/0.492. These data were then integrated and used to predict the warfarin dose associated with therapeutic anti-coagulation defined as an International Normalized Ratio (INR) of 2.0,3.0. The maximum prothrombinopenic response to warfarin in cats after a single intravenous dose of 0.5 mg/kg occurred at 24,48 h. Pharmacodynamic modeling suggested that each cat had a narrow therapeutic range of the steady-state concentration of total warfarin required to appropriately block prothrombin complex synthesis (median: 265.2,358.7 ng/mL). The median daily dose range predicted to yield therapeutic concentrations of warfarin was 0.061,0.088 mg/kg per day. Wide inter-individual variations in both pharmacokinetics and pharmacodynamic response suggest that a more optimal dosing of warfarin may be possible with the development of individual pharmacokinetic/pharmacodynamic algorithms, analogous to those currently employed in human patients. [source] Literacy as a complex activity: deconstructing the simple view of readingLITERACY, Issue 2 2008Morag Stuart Abstract The Rose Review into the teaching of early reading recommended that the conceptual framework incorporated into the National Literacy Strategy Framework for Teaching , the Searchlights model of reading and its development , should be replaced by the Simple View of Reading. In this paper, we demonstrate how these two frameworks relate to each other, and show that nothing has been lost in this transformation from Searchlights to Simple View: on the contrary, much has been gained. That nothing has been lost is demonstrated by consideration of the underlying complexity inherent in each of the two dimensions delineated in the Simple View. That much has been gained is demonstrated by the increased understanding of each dimension that follows from careful scientific investigation of each. The better we understand what is involved in each dimension, the better placed we are to unravel and understand the essential, complex and continual interactions between each dimension which underlie skilled reading. This has clear implications for further improving the early teaching of reading. [source] Human duodenal phase III migrating motor complex activity is predominantly antegrade, as revealed by high-resolution manometry and colour pressure plotsNEUROGASTROENTEROLOGY & MOTILITY, Issue 4 2002J. M. Andrews Abstract,Late phase III migrating motor complex activity has been said to be primarily retroperistaltic but has not been assessed with high resolution manometry or three-dimensional colour pressure plots (pressure/time/distance). Duodenal phase III was examined in healthy young volunteers (seven male, two female) with a 20-lumen assembly. With the most proximal sidehole in the distal antrum, after a 4.5-cm interval 18 sideholes at 1.5-cm intervals spanned the duodenum with a final sidehole 3 cm beyond. Fasting pressures were recorded until phase III occurred. Comparisons were made between proximal (P) and distal (D) duodenum during early (E) (first 0.5,1 min) and late (L) (last 0.5,1 min) phase III. With colour pressure analysis, 121 of 180 pressure wave (PW) sequences were purely antegrade, two purely retrograde and 57 bidirectional. Ten of fifty-seven bidirectional PW sequences were complex, branching to become two separate sequences. Bidirectional sequences occurred more frequently in late than early phase III (L 43 vs. E 14 of 57), but their occurrence did not differ between proximal and distal duodenum (P31 vs. D 24 of 57). Antegrade propagation velocity was faster in late compared with early phase III (L 28.50 vs. E 17.05 mm s,1; P = 0.006), but did not differ between proximal and distal duodenum. Colour pressure analysis also indicated an intermittent segmental pattern to phase III, with each subject exhibiting a change in velocity or direction, or a relative failure of peristalsis somewhere along the duodenum during part of phase III. Duodenal phase III is not homogenous and, in contrast with previous studies, does not primarily constitute a retroperistaltic pump. Colour pressure analysis is useful in interpreting intraluminal pressure profiles and may improve the sensitivity and specificity of clinical studies. [source] | ||||||||||||||||